I have 45x40 floor space behind my 2nd row. 45" wheel well to well an 40" from back of 2nd row seat to rear gate. I kno I need to be a few inches from rear gate, so I figure 45x34 an I want to go 15" high. So is 45x34x15 rite or is there sum special ratio that needs to be used? I most likely will have my box built, it's jus 3-4 months down the way. An if I can get enough info by then I may make an attempt my self.